1. Field of the Invention
The present invention relates, in general, to devices for intercepting stagnant water and, more particularly, to a device for intercepting stagnant water, which prevents the water stagnated in an earth and sand layer from leaking out of a retaining wall.
2. Description of the Prior Art
Generally, when a great quantity of concrete is applied so as to construct a significantly large structure, such as a retaining wall, a plurality of small holes are made in the concrete while moisture in the concrete is evaporated in the process of hardening the concrete. Such small holes cause the concrete structure to be cracked as the concrete structure is contracted and expanded due to the atmospheric temperatures.
Since the stability of the structure is threatened if cracks are generated in the concrete structure and water is infiltrated into the concrete structure through the cracks, the generation of the cracks should be prevented or the interception of water should be performed.
In the past, there were used techniques wherein the water infiltrated into the concrete structure was discharged out of the structure by the installation of a plurality of water discharge conduits. Of the techniques, a technique wherein panels made of glass fiber were inserted into the retaining wall and the water infiltrated into the retaining wall was guided by the glass fiber panels was disclosed in U.S. Pat. No. 5,845,456.
In order to prevent concrete structures from being cracked due to the contraction and expansion of concrete, there was proposed a technique wherein a wide construction area was divided into small structure units and expanding and contracting strip members were disposed between the structure units.
However, according to the above technique, though the cracks are prevented because spaces exist between the structure units, water leaks through the spaces where the expanding and contracting strip members are disposed, thereby threatening the stability of the construction structure.
Therefore, as shown in FIG. 1, stagnant water intercepting members 20 should be installed additionally in a retaining wall that is constructed at a place that water is easy to infiltrate, such as an underground road, a tunnel, an underground garage, an underground water reservoir and a mountain road, so as to prevent water from leaking through the spaces between the divided construction structures.
Each of the stagnant water intercepting members 20 is fitted into a space between the two expanding and contracting strip members 10 and 10' at its center at a right angle. The retaining wall W is constructed by applying concrete around the stagnant water intercepting members 20.
Such a stagnant water intercepting member 20 is made of soft material, such as soft PVC or rubber, and is formed by integrating into a single body the center portion, which is disposed in the expanding and contracting strip member, and the side wing portions, which are disposed in the concrete. The shape of the stagnant water intercepting member 20 is generally as illustrated in FIG. 1.
When time lapses after an stagnant water intercepting member of soft PVC or rubber is laid in the concrete and the concrete is hardened, the entire surface of the stagnant water intercepting member becomes separated from the concrete, thereby generating a gap between the stagnant water intercepting member and the concrete. Consequently, as illustrated by arrows in FIG. 1, water, which flows into the retaining wall W along one expanding and contracting strip member 10', passes through a gap between the stagnant water intercepting member and the concrete and, subsequently, leaks out of the retaining wall W through another expanding and contracting strip member 10.